Climate models

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Crowdsourcing air pollution measurements: iSPEX-EU 2015

September 06, 2015

A collaboration led by researchers at Leiden University in The Netherlands has launched a Europe-wide citizen campaign—iSPEX-EU 2015—to use a smartphone add-on and app to measure atmospheric aerosols (tiny particles), resulting in a broad-based data set with high spatio-temporal resolution.

Atmospheric aerosols play an important but as-yet poorly understood role in climate and air quality, with significant impacts on the environment, health, and air traffic. Satellite-based aerosol monitoring is, despite its global coverage, limited in spatial and temporal resolution (with global coverage up to once a day with a ground resolution of a few kilometers only), and lacks sufficient information on aerosol particle characteristics. Therefore, the researchers say, a different strategy is needed to overcome these current limitations.

November 02, 2014

The UN Intergovernmental Panel on Climate Change (IPCC) released the Synthesis Report that distills and integrates the findings of the full IPCC Fifth Assessment Report (AR5) released over the past 13 months. The report expresses with greater certainty than in previous assessments that emissions of greenhouse gases and other anthropogenic drivers have been the dominant cause of observed warming since the mid-20th century.

The report expressed with medium confidence that the period from 1983 to 2012 was likely the warmest 30-year period of the last 1,400 years in the Northern Hemisphere, where such assessment is possible. The report also noted that the globally averaged surface temperature exhibits substantial decadal and inter-annual variability. Due to this natural variability, trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends. As one example, the rate of warming over the past 15 years (1998–2012; 0.05 [–0.05 to 0.15] °C per decade), which begins with a strong El Niño, is smaller than the rate calculated since 1951 (1951–2012; 0.12 [0.08 to 0.14] °C per decade). [The much discussed “pause”.]